"Dak galbi is another spicy, stir-fried chicken dish that all Koreans seem to love. The main dish between this and other spicy dishes is the addition of cabbage and usually perilla leaves, giving it a distinct and satisfying aroma. There are many dak galbi restaurants/quasi-bars that set up a single, large frying pan in the center of the table for everyone to enjoy the meal together (Koreans literally love eating together). Serve with rice."
Heat oil in a large nonstick saucepan. Add chicken pieces; cook and stir until nearly opaque, 4 to 7 minutes.
Combine gochujang, soy sauce, gochugaru, mirin, brown sugar, sesame oil, garlic, black pepper, and ginger in a bowl. Add to the saucepan with the chicken. Cook and stir until chicken pieces are browned and well coated, 3 to 5 minutes.
Stir rice cakes, cabbage, sweet potato, and onion into the skillet with the chicken mixture. Cook until sweet potato changes color, about 10 minutes. Add 2 to 2 1/2 scallions and perilla leaves. Cook until wilted, about 3 minutes. Add more water if sauce seems to be drying up. Garnish with remaining scallions and sesame seeds.
Chicken thighs can be substituted for the breasts, if desired.
Use any cooking wine you prefer.
In Korean restaurants (and now at home, too) it's common to add some more rice, gim (dried seaweed), and sesame oil to the remaining sauce in the pan. Mix it together well and this will provide a great, last bite to your meal.